{"id":"CVE-2026-58271","revision":"8665e40cb727460e87fb89d52f351d35","records":[{"revision":"8665e40cb727460e87fb89d52f351d35","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-58271","aliases":[],"title":"@sync-in/server vulnerable to TOTP Brute-Force via `POST /api/app/sync/register`","description":"Sync-in Server is an open-source platform for file storage, sharing, collaboration, and syncing. Prior to version 2.4.0, `POST /api/app/sync/register` accepts credentials and a TOTP code to register a desktop sync client. On a failed TOTP, `SyncClientsManager.register()` calls `updateAccesses(user, ip, false)`, which hits a freeze branch that writes `passwordAttempts` back unchanged. The counter never reaches `USER_MAX_PASSWORD_ATTEMPTS` (10) and the lockout gate never fires. A successful guess returns a `{clientId, clientToken}` pair. The token can be exchanged via `POST /api/app/sync/auth/cookie` for a full JWT. While the code is valid, the attacker can also call `POST /api/auth/2fa/disable` to permanently remove MFA. Version 2.4.0 patches the issue.","state":0,"publishedAt":"2026-09-21T19:50:14.539+00:00","modifiedAt":"2026-09-24T22:36:41.527+00:00","affected":[{"ecosystem":"Vendor product","name":"server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Sync-in\",\n                    \"product\": \"server\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 2.4.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","score":6.8,"severity":"MEDIUM"}],"references":["https://github.com/Sync-in/server/security/advisories/GHSA-274f-6w77-8qm9"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-58271","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-58271","identifiers":["CVE-2026-58271"]},"retained":false,"historicalAffected":[]}],"coverage":[]}